Tension device for shuttles



June 17, 1930. L. c. BALDWIN 1,764,7

TENSION DEVICE FOR SHUTTLES Filed Oct. 12, 1928 H lfivc nfork 5' my Lathr z yd zamv o Fig." 1 is a Patented June 17, 1930 UNITED STATES PATENT OFFICE 1 LUTHER c. BALDWIN, onriaovrnnncn, m-Ionn'IsLAnn, assienonro U. s. nominee SHUTTLE cor/[ranger rnovxnnncn, :eHoDn ISLAND, A CORPORATION or nrtonn I? I$LAND TENSION Davie-n FOR SHUTTLES Application filed ember iaisesg swarm. 312,112.

This inventionpertains to weaving shuttles and more particularly to yarn tension devices forsuch shuttles. \Vhile certainlot the broader features of the invention may find embodiment in other specific arrange- .ments at large, for example as disclosedin my copending application Serial No. 312,111, filed October 12, 1928, I have herein chosen ,to. illustrate the tension device of the present .invention as embodied in a removable block or housing of metal or other material inde- .pendent of but adapted to seat within a cavity in the shuttle body. By reason of the peculiar .conditions'under Whicha shut- ,tle operates, it is far more diflicult to keep a uniform tension on the moving yarnthan in most other situations, sincesuch apparently negligible quantities as the inertia of the tension element become of importance in shuttle tensions in view of the extremely sudden changes in velocity and directions of movement of the shuttle. In the small spaceavailable for the reception of a shuttle tension device, the utmost compactness of arrangement is essential, thus precluding" the useot many types of tension elements which are found useful in other situations. The parts should be sturdy and. capable of long ,continuous use, although readily replaceable when worn or broken, The tension should i be so designed as to permit ready and rapid threading, and to avoid'cutting' or breaking of the yarn, espec1ally when the direction of motion of the shuttle 1s changed. The

1,35 yarn engaging elements; should be so ar ranged and of such materlal asto resist rapid cutting or wear by the movingyarn;

inertia eii'ects should be minimized ;T and the device should be simple and inexpensive 4:0 to construct and install.

In accordance with th'e'presentinvention I provide a tenslon device possessing all of the above desirable characterist cs together with other features more fully pointed out i .1 5 hereinafter.

In the accompanying drawings I have,

illustrated certain embodiments of the invention byway of example and in the drawings. 1 i T fragmentary plan view of a vention installed therein;

Fig.2 is a fragmentary side elevationof the shuttleillustrated in Fig. 1-; Fig. 3 is a side elevation of agremovable tension block embodying-a preferred form of the present invention;

elis a section, to larger scale, on the line 4l-4 of Fig. .3; i I

Fig. .5 is a horizontal section, to larger scale, on the line 55 of'Fig. 3; I

6 is a sile elevat'o'n similarto Fig.3, but illustrating another embodiment,

Fig. 7 is a rear end elevation'of the device, shown in Fig. 6; i I

Fig. 8 is an elevation showing'the device of Fig. 6 from theopposite side; and

F ig. 9 is a Vertical section, to larger scale, substantially on the line 99 of Fig. 6. 7

Referring. to the drawings'and particularly to Figs. 1 and 5 inclusive, the numeral 1 designates the shuttlebody, havingthe usual bobbin cavity2 and tension receiving;

cavity inits end portion 3. The shuttle is." j I also. provided with a yarn delivery eye 4 at the outer end ofa passage lea-ding laterally from the tension cavity. 1 i

.In accordance with thepresent invention the tension elements are carried by a blockslot 7 together with such other ,andxusual thread guidingand retaining parts as arecommon in devices? of this type, including, for example. the downwardly extending front horn I-I. The block5gis also preferably provided with a downwardly extending boss 8 adapted to seat in a socket in the bot- 9 tom of the tension receiving cavity, and with a transverseopening 9 for the reception of the usual retaining: bolt 10. (Fig.1)

In accordance with the present invention the block or housing 5is provided with a. substantially vertical and preferably cylindrical bore 11 (Fig. 4;) extending upwardly from its bottom surface. Within'this bore Iarrange a pair of relatively movable ten- .sion elements12 and 13 respectively.- Prefthe block from the cavity bothtension elements are free to bewithdrawn from the bore 11. The upper tension element 12 is arranged to slide freely in the bore 11 and is urged downwardly toward the lower element 13 by means of a spring 14. The upper 'end of this spring preferably bears against a shoulder on an adjusting screw 15 engaging a screw-threaded bore 16 in the upper part ofthe block 5. In order to hold the screw 15 in adjusted position I may if de-, sired provide retaining means as, for example, a set'screw 17 engaging a screwthreadedbore in the block 5. Under some circumstances the spring .14 may be dispen's ed with, the weightofthe friction element 12 being depended upon to secure the proper tension. In such case a series of interchangeable members 12 may be provided,-ofdifferent weights adapted for selective use in accordance with the size of the yarn or the degree of. tension required.

Preferably the members 12 and 13 are provided with substantially flat end surfaces opposed to each other and between which the yarn-Y- passes, such opposed surfaces being substantially in the plane of the bottom of channel 6. To .facilitatethe entrance of the yarn between the members 12 and 13 I prefor to round the corners of the elements 12 and 13 where their end surfaces merge into flaring throat 18 into which the yarn may be pulled in order to wedge the members 12 and 13 apart. p I

In accordance with the arrangement shown in Figs. 1 to 5, the yarn engaging surfacesof the members 12 and 13 are continuous (without projections 'or perforations) and as these elements are substantially fiat and p'arallehthey bear with equal pressure over that portion of the yarn which is disposed bet-wee'nthem. The-pressure being thusjdistributed over asubstantial length of yarn produces amor'e unifornrtens'ion than would be the case were the yarn pinched at a single point, and as the yarn extends in a substant ally straight run acrossthe tension member 13, there are no turns or bends tend-.

ing to produce areas of abnormal thickness which would localize the pressure.

Inorder to guide the yarn properly ina straight'ru'n across the tension elements I prefer to provide a pair of fixed guide pins 19 and 20 (Fig. 5) disposed respectively at opposite sides of the tension elements. The pin 20 is arranged closely adjacent to one side of the channel 6 while the pin 19 is disposed ata point substantially laterally opposite to the yarn delivery eye 4. The yarn thus moves in a substantially straight run from the'channel 6, across the surface of the tension element 13, and then makes a substantially right angle in turning about the post 19 on its way to the yarn delivery eye 4.

In the arrangement shown in Figs. 6 to 9 inclusive the block 5 is substantially similar to the block 5 above dcscribed and is provided with a bore 11 for the reception of the upper and lower tension elements 12 and 13 similar to the elements 12 and 13 above described.

In this instance the elements 12 and 13 lower end against the tension element 12 and at its upper end against the. web 22 'forming'the upper wall of the cavity 11.

In the arrangement just described the guide post 19 and also the post 20, if desired, may be omitted, since the'pin 21 which passes down through the friction elements constitutes a guide'abont which the yarn passes on its way to the lateral guideeye. latter arrangement may be desirable under some circumstances, I prefer that disclosed in Figs. 1 to 5 inclusive, since in the latter case the yarn passes in a straight run across the tension elements, thus ensuring more uniform tension than when yarn isconstrained to make 'a sharp bend or angle at a point 4 between thetension elements. H1611 cylindrical surfaces, thus providing a} As already pointed out, the cup-shaped tension elements are made very light in weight so as to avoid inertia effects such as might pinch, cut, or break the yarn when the direction of movement of the shuttle is suddenly changed. As the tension elements are disposed within theblock 5 they are not readily affected by accumulations of lint or oil and are fully protected against mechanical injury. Thetension spring, if such be used, is also housed. in and protected, al-

though its tension is readily adjustable.

The tension elements are of simple, durable, and compact form, taking up but little room in the shuttle body and being readily formed A spring 14 may be ar-. ranged within the bore 11, hearing at its \Vhile this shocks and blows to which the shuttle is subjected in use.

various changes in size, shape and relative arrangement of parts may readily be made without departing from the spirit of the invention.

I claim:

" having an elongate bore therein, a pair of tension elements fitting in slidable engagement with the walls of the bore within said bore, one at least of said elements sliding longitudinally of said bore toward and from the other tension element, said elements having continuous yarn engaging faces, bearing with equal pressure over that portion of the yarn disposed between them, and means re sillently urging the movable element toward the other. i

2. A shuttle tension comprisinga housing removably secured in the shuttle and having an elongate bore, a pair of tension elements fitted within'said bore, one at least of said elements sliding longitudinally of the bore toward ;and from the other element, and 1 guide means in the shuttle beyond the confines of said elements for determining the paths of a yarn passing between them.

3. A shuttle tension comprising a housing having an elongate cylindrical bore, and a pair of cylindrical tension elements fitted in slidable engagement with the walls of said bore, one at least of said elements sliding longitudinally of'the bore toward and from the other element, the opposed surfaces of said elements being uninterrupted and free from projections or apertures and hearin g throughout with equal pressure over that portion of the yarn disposed between them. y

4. A shuttle tension'comprising a housing removably secured in the shuttle and having an elongate bore therein, and a pair of tension elements fitted in slidable engagement with the walls of said bore, one

at least of said elements sliding longitudinally of the bore toward and trom'the other element, the opposed surfaces of said elements being smoothly polished and imperforate and bearing throughout with portion of the yarn bore, a spring seated within the hollow of the latter eleinent, and-means tor' adjustably tensioning the spring. f

ing removably secured in the shuttle and having anelongate cyhndrical bore .anda

pair of thin-walled,lightweight, cup-like.

tension elements fitting inslidable' engage ment with the walls of the bore insaidbor'e,

. said elements having flauparallel" opposed 1. Ashuttle tension comprising a housing end walls constituting'yarn engaging sur-. faces, the {junction between the said end wallsand thefsid-e walls of said elements being smoothly roundedto provide a flaring throat to facilitate entrance of theyarn between the elei'i'ients. I l V v 7. A shuttle tension comprising a block "adapted to be seated in a cavity in a shuttle body, said block having a bore extending upwardly from its bottom face, -a pair of tension elements fittingw1th1n SELlCl b0re,

thelower of said elements 'restingupon the bottomcf the cavity in the shuttle body when the 'block is assembled :with the latter, the upper tension element sliding vertically in the bore and means for holding said elements tens onally in engagement, said elements being removable from and replaceable inthe block without altering the. tension exerted by such means durmg operative engagement thereof.

S. The combination with shuttle'body provided with accavity for the rcception of tension means of a block fitted within said cavity, the block having a cylindrical bore extending upwardly from its lower face,"

and a pair or" cup-like tension members slidably fitting in said bore, the lower of said members being inverted and adaptedto rest on the bottom of the cavity in the shuttle body when the block is seated therein.

9. The combination with a shuttle body provided with arcavity torthe reception of tension means, of a block fitted within said cavity, the block having a cylindrical bore,

a pair of relatively movable tension elements slidably fitting in said bore, said elemerits having opposed substantially fiat yarn engaging surfaces, and yarn guide elements in said shuttle independent of said block for directing the yarn in a path eX-' tending between said elements.

1 0. Thecombination with a shuttle body provided with a cavity for the reception of tension means, of a block fitted within said cavity, the block having a cylindrical bore,

a pair of relatively movable cylindrical tension elements slidably fitting in said bore, said 'elements having substantially smooth, imperforate yarn engaging faces, and yarn guide members disposed at opposite sides of' said tension elements and constraining the yarn to move in a substantially rectilinear path extending between said elements.

11 .111 combination witha shuttle body provlded with a cavity tor the reception 6. A shuttle tension"comprising a housof tension means and having a passage leading from said cavity to a lateral guide eye, a block fitting within said cavity, the block having a bore extending upwardly from its bottom, a pair of relatively movable tension elements disposed within said bore and having yarn engaging surfaces parallel to the plane of the bottom of said bore, a

spring urging one of said elements toward the other, a screw for adjusting the tension of the spring, means for retaining the screw in adjusted position, and a pair of yarn guides so arranged as to direct the yarn longitudinally of the shuttle body and between said tension elements and laterally to the guide eye.

12. A tension device for shuttles comprising a block having a longitudinal channel forthe passage of the yarn, a pair of relatively movable tension elements adjacent to the forward end of the channel, said elements having opposed substantially fiat yarn engaging surfaces disposed adjacent and parallel to the plane of the bottom of said channel, said elements having, rounded e es providing a throat for the entrance of the yarn between them, the block having ,a threading slot leading downwardly and laterally into said channel, and a pair of spaced fixed guides for determining the path of the yarn between the tension elements.

l Signed by me at Providence, Rhode Island, this 9th day of October, 192-8.

- LUTHER C. BALDVIN. 

